1. Field of the Invention
The present invention relates electric push rod design for use in an electric bed, massage chair, exercising machine, physical therapy equipment or the like to move movable component parts and more particularly, to an electric push rod and release mechanism combination structure, which uses a release mechanism consisting of a mounting socket, a connection socket, a torsion spring, a clutch module and an operating device for operation by a user to release the retractable tube set of the electric push rod from the movable component parts of the equipment safely with less effort.
2. Description of the Related Art
An electric push rod is adapted for use in an electric bed, massage chair, exercising machine, physical therapy equipment or the like to move movable component parts in lifting a person or load carried thereon, or biasing the angle of the person or load.
An electric push rod for this purpose generally comprises a retractable tube set, a motor operable to move the retractable tube set between an extended position and a received position, and a clutch mechanism operable to disengage the retractable tube set from the equipment in which the electric push rod is installed for enabling the retractable tube set to be retracted rapidly. However, the clutch mechanism cannot control the retracting speed of the retractable tube set. When the retractable tube set is retracted rapidly to lower the person or load carried on the movable component parts of the equipment, the person or load carried on the movable component parts of the equipment may feel uncomfortable, or the load may be impacted, causing damage.
FIG. 10 illustrates an electric push rod release control mechanism according to the prior art. This design comprises a first socket A connected to a retractable tube set D1 of an electric push rod D, a second socket B movably attached to the first socket A, a coupling D2 fastened to the second socket B and connectable to a movable frame part of an external equipment (electric bed, massage chair, physical therapy equipment, etc.), and a clutch module C mounted at the second socket B. The clutch module C comprises a barrel C, a first ring member C2 and a second ring member C3. If the user does not release the second ring member C3, the stop block C31 of the second ring member C3 will be stopped at the flange C11 of the barrel C1. At this time, the first ring member C2 and the second ring member C3 clamp the barrel C against movement. Subject to engagement between the protruding portions C12 of the barrel C1 and the recessed portions B1 of the second socket B, the retractable tube set D1 can move the coupling D2 and the movable frame part of an external equipment.
When released the second ring member C3, the second ring member C3 is separated from the first ring member C2 to disengage the stop block C31 from the flange C11 of the barrel C1. At this time, the retractable tube set D1 can be retracted, allowing the movable part of the external equipment to be lowered rapidly. If the movable part of the external equipment carries a person or heavy load, the person or heavy load will accelerate the lowering speed of the movable part of the external equipment, threatening the user or the person carried on the movable part of the external equipment, or causing the load to be impacted or damaged. Thus, an improvement in this regard is necessary.